Method of Manufacturing Semiconductor Device and Non-transitory Computer-readable Recording Medium

ABSTRACT

Described herein is a technique capable of detecting a substrate state without contacting the substrate. According to one aspect of the technique, there is provided (a) loading a substrate retainer, where a plurality of substrates is placed, into a reaction tube; (b) processing the plurality of the substrates by supplying a gas into the reaction tube; (c) unloading the substrate retainer out of the reaction tube after the plurality of the substrates is processed; and (d) detecting the plurality of the substrates placed on the substrate retainer after the substrate retainer is rotated by a first angle with respect to a transferable position, wherein the plurality of the substrates is transferable to/from the substrate retainer in the transferable position.

CROSS REFERENCE TO RELATED APPLICATIONS

This non-provisional U.S. patent application is a continuation of U.S.patent application Ser. No. 16/774,992, filed Jan. 28, 2020, which is acontinuation of International Application No. PCT/JP2017/027474, filedon Jul. 28, 2017, the entire contents of which are hereby incorporatedby reference.

TECHNICAL FIELD

The present disclosure relates to a method of manufacturing asemiconductor device for processing a substrate and a non-transitorycomputer-readable recording medium.

BACKGROUND

A substrate (also referred to as a “wafer”) may be processed by asubstrate processing apparatus (hereinafter, also simply referred to asa “processing apparatus”) including a substrate retainer (also referredto as a “boat”) configured to accommodate (support) a plurality ofsubstrates including the substrate in multiple stages and a transportdevice configured to transport (transfer) the plurality of thesubstrates to the boat. Specifically, the boat is transferred (loaded)into a process furnace of the processing apparatus while the pluralityof the substrates is supported by the boat, and the plurality of thesubstrates is processed in the process furnace. According to theprocessing apparatus, when a temperature of the substrate is increased(elevated) in the process furnace, or when the substrate is transferredout of the process furnace and cooled, an abnormality (also referred toas an “error”) such as cracking and warping of the substrate may occurin the substrate due to the thermal stress. When the cracking or thewarping is at a level that the substrate cannot be automaticallytransferred by an automatic substrate transfer mechanism, a substrateholder (hereinafter also referred to as “tweezers”) configured to hold(support) the substrate while the substrate is transferred may collidewith the substrate, and the boat may fall by colliding the substrateholder. As a result, serious accidents, such as the damage to componentsof the processing apparatus (for example, a component made of quartz)may occur.

In order to address the problem described above, a mechanism configuredto detect a state of the substrate may be provided. For example,according to related arts, the transport device is provided with a photosensor. The photo sensor is moved along a vertical axis of the transportdevice, and the substrate on the substrate holder is detected by thephoto sensor.

SUMMARY

Described herein is a technique capable of detecting a state of asubstrate without contacting the substrate by a mechanism configured todetect the state of the substrate even when an abnormality occurs in thesubstrate.

According to one aspect of the technique of the present disclosure,there is provided a method of manufacturing a semiconductor deviceincluding: (a) loading a substrate retainer, where a plurality ofsubstrates is placed, into a reaction tube; (b) processing the pluralityof the substrates by supplying a gas into the reaction tube; (c)unloading the substrate retainer out of the reaction tube after theplurality of the substrates is processed; and (d) detecting theplurality of the substrates placed on the substrate retainer after thesubstrate retainer is rotated by a first angle with respect to atransferable position, wherein the plurality of the substrates istransferable to/from the substrate retainer in the transferableposition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically illustrating a substrateprocessing apparatus preferably used in one or more embodimentsdescribed herein.

FIG. 2 is another perspective view schematically illustrating thesubstrate processing apparatus shown in FIG. 1.

FIG. 3 schematically illustrates a wafer abnormality detection device asan example of transport information detection mechanism preferably usedin the embodiments described herein.

FIG. 4 schematically illustrates an example of a controller of asubstrate processing system configured to control a plurality ofsubstrate processing apparatuses preferably used in the embodimentsdescribed herein.

FIG. 5 is a block diagram schematically illustrating a configuration ofthe controller and related components of the substrate processing systempreferably used in the embodiments described herein.

FIG. 6 schematically illustrates an example of a wafer detectionoperation using the wafer abnormality detection device shown in FIG. 3.

FIG. 7 schematically illustrates the example of the wafer detectionoperation using the wafer abnormality detection device shown in FIG. 6when viewed from above.

FIG. 8A schematically illustrates another example of the wafer detectionoperation using the wafer abnormality detection device preferably usedin the embodiments described herein when viewed from above.

FIG. 8B schematically illustrates another example of the wafer detectionoperation using the wafer abnormality detection device preferably usedin the embodiments described herein.

FIG. 9 schematically illustrates the wafer detection operationpreferably used in the embodiments described herein.

FIG. 10 is a flow chart schematically illustrating an exemplary sequenceof a substrate processing according to the embodiments described herein.

DETAILED DESCRIPTION Embodiments

Hereinafter, one or more embodiments (hereinafter, simply referred to as“embodiments”) according to the technique of the present disclosure willbe described with reference to the drawings. According to the best modeof the present disclosure, a substrate processing apparatus(hereinafter, also simply referred to as a “processing apparatus”) isconfigured as a vertical type substrate processing apparatus capable ofperforming a process such as an oxidation process, a diffusion processand a CVD (Chemical Vapor Deposition) process to a substrate. Forexample, the processing apparatus is used to perform a method ofmanufacturing a semiconductor device such as an integrated circuit (IC).

As shown in FIGS. 1 and 2, a substrate container (hereinafter, alsoreferred to as a “pod”) 110 serving as a carrier configured toaccommodate a plurality of substrates including a substrate (alsoreferred to as a “wafer”) 200 may be used in a substrate processingapparatus 100. The substrate processing apparatus 100 includes a housing(also referred to as a “pressure-resistant housing”) 111. A frontmaintenance port 103 is provided at a lower front side of a front wall111 a of the housing 111 in order to maintain the substrate processingapparatus 100. A pair of front doors 104 is provided at the frontmaintenance port 103. The pair of front doors 104 functions as anopening/closing mechanism configured to open or close the frontmaintenance port 103. A pod loading/unloading port 112 is provided atthe front wall 111 a of the housing 111 so as to communicate with aninside and an outside of the housing 111. The pod loading/unloading port112 is opened or closed by a front shutter 113.

A loading port 114 is provided at a front side of the podloading/unloading port 112. The loading port 114 is configured such thatthe pod 110 is aligned while placed on the loading port 114. The pod 110is transferred (loaded) onto the loading port 114 and transferred(unloaded) out of the loading port 114 by an in-process transfer device(not shown).

A rotatable pod shelf 105 is provided over a substantially centerportion of the housing 111. The rotatable pod shelf 105 is configured tohold (store) a plurality of pods including the pod 110. The rotatablepod shelf 105 includes a vertical column 116 capable of rotatingintermittently along a horizontal direction and a plurality of shelfplates (also referred to as “substrate container placement tables”) 117provided in a radial direction at an upper end portion, a mid portionand a lower end portion of the vertical column 116. Each of theplurality of shelf plates 117 is configured to support a pod such as thepod 110 placed thereon.

A pod transfer device 118 is provided between the loading port 114 andthe rotatable pod shelf 105 in the housing 111. The pod transfer device118 includes: a pod elevator (also referred to as a “pod elevatingmechanism”) 118 a configured to elevate and lower while supporting thepod 110; and a pod transfer mechanism 118 b. The pod transfer device 118transfers the pod 110 among the loading port 114, the rotatable podshelf 105 and a pod opener 121 by consecutive operations of the podelevator 118 a and the pod transfer mechanism 118 b.

A sub-housing 119 is provided below the substantially center portion inthe housing 111 toward a rear end of the housing 111. A pair of waferloading/unloading ports 120 configured to load and unload the wafer 200serving as the substrate into and out of the sub-housing 119 is providedat a front wall 119 a of the sub-housing 119. The pair of waferloading/unloading ports 120 is arranged vertically in two stages. A pairof pod openers including the pod opener 121 is provided at the pair ofthe wafer loading/unloading ports 120, respectively. For example, anupper pod opener and a lower pod opener may be provided as the pair ofthe pod openers. The upper pod opener and the lower pod opener may becollectively or individually referred to as the “pod opener 121”. Thepod opener 121 includes a placement table 122 where the pod 110 isplaced thereon and a cap attaching/detaching mechanism 123 configured toattach or detach a cap of the pod 110. By detaching or attaching the capof the pod 110 placed on the placement table 122 by the pod opener 121,a wafer entrance of the pod 110 is opened or closed.

The sub-housing 119 defines a transfer chamber 124 fluidically isolatedfrom a space (hereinafter, also referred to as a “pod transfer space”)in which the pod transfer device 118 or the rotatable pod shelf 105 isprovided. A wafer transport mechanism (also simply referred to as a“transport mechanism”) 125 is provided at a front side portion of thetransfer chamber 124. The wafer transport mechanism 125 includes a wafertransport device (also simply referred to as a “transport device”) 125 aand a wafer transport device elevator 125 b. The wafer transport device125 a is capable of horizontally rotating or moving the wafer 200. Thewafer transport device elevator 125 b is capable of elevating orlowering the wafer transport device 125 a.

As shown in FIG. 3, a wafer abnormality detection device (hereinafter,also simply referred to as a “wafer detection device”) 400 configured todetect a transport state of the wafer 200 is attached to the wafertransport device 125 a. For example, as shown in FIG. 3, the waferabnormality detection device 400 is constituted by a pair of detectionarms 401 rotatably attached to both sides of the wafer transport device125 a and an actuator (not shown) configured to drive (rotate) the pairof the detection arms 401. Each of the detection arms 401 is providedwith a wafer position detection sensor S1 (hereinafter, also simplyreferred to as a “sensor S1”) and a wafer jump-out detection sensor S2(hereinafter, also simply referred to as a “sensor S2”). As describedabove, even when the wafer 200 jumps out (that is, when a wafer jump-outoccurs), it is possible to detect the wafer jump-out of the wafer 200 bythe sensor S2. In FIG. 3, the illustration of a boat 217 is omitted.

As schematically shown in FIG. 1, the wafer transport device elevator125 b is provided between a right end of the front portion of thetransfer chamber 124 of the sub-housing 119 and a right side end of thepressure-resistant housing 111. The wafer transport device 125 a isfurther includes tweezers (also referred to as a “substrate holder”) 125c capable of supporting the wafer 200. Using the tweezers 125 c to placethe wafer 200 thereon, the wafer transport mechanism 125 is configuredto charge or discharge the wafer 200 into or out of the boat (alsoreferred to as a “substrate retainer”) 217 serving as a placement portof the wafer 200 by consecutive operations of the wafer transport deviceelevator 125 b and the wafer transport device 125 a.

A standby space 126 where the boat 217 is accommodated in standby stateis provided at a rear side portion of the transfer chamber 214. Aprocess furnace 202 is provided above the standby space 126. A lower endof the process furnace 202 may be opened or closed by a furnace openingshutter (also referred to as a “furnace opening opening/closingmechanism”) 147. A boat elevator 115 is provided between a right end ofthe standby space 126 of the sub-housing 119 and the right side end ofthe pressure-resistant housing 111. The boat elevator 115 is configuredto elevate or lower the boat 217. An arm 128 serving as a couplingcomponent is connected to an elevating table (not shown) of the boatelevator 115. A seal cap 219 is provided horizontally at the arm 128. Aboat rotating mechanism 129 configured to rotate the boat 217 isprovided at the seal cap 219.

The seal cap 219 is configured to support the boat 217 vertically andconfigured to close the lower end of the process furnace 202. The boat217 includes a plurality of support columns 220 serving as a pluralityof supporting components provided with slots (grooves). The slots of theplurality of the support columns 220 are configured to support theplurality of the wafers including the wafer 200 in multiple stages. Theboat 217 is configured to support the plurality of the wafers (forexample, 50 wafers to 200 wafers) while each of the plurality of thewafers is horizontally oriented and concentrically arranged in thevertical direction by the slots of the plurality of the support columns220.

A clean air supply mechanism 134 is provided at a left end of a leftside portion of the transfer chamber 124 opposite to the boat elevator115 and the wafer transport device elevator 125 b. The clean air supplymechanism 134 is configured to supply clean air 133 such as an inert gasand a clean atmosphere. The clean air supply mechanism 134 includes asupply fan (not shown) and a dust-proof filter (not shown). A notchalignment device (not shown) serving as a substrate alignment deviceconfigured to align a circumferential position of the wafer 200 isinstalled between the wafer transport device 125 a and the clean airsupply mechanism 134.

The clean air 133 ejected from the clean air supply mechanism 134 flowsaround the notch alignment device, the wafer transport device 125 a andthe boat 217 accommodated in the standby space 126. Thereafter, theclean air 133 is exhausted from the housing 111 through a duct (notshown), or the clean air 133 is circulated back to a primary side(supply side) of the clean air supply mechanism 134 and then ejectedagain into the transfer chamber 124 by the clean air supply mechanism134.

Hereinafter, the operation of the substrate processing apparatus 100preferably used in the embodiments will be described with reference toFIGS. 1 and 2. When the pod 110 is placed on the loading port 114, thepod loading/unloading port 112 is opened by the front shutter 113. Thepod 110 placed on the loading port 114 is loaded (transferred) into thehousing 111 through the pod loading/unloading port 112 by the podtransfer device 118.

The pod 110 loaded into the housing 111 is automatically transferred toand temporarily stored in a designated shelf plate among the pluralityof shelf plates 117 of the rotatable pod shelf 105 by the pod transferdevice 118. Thereafter, the pod 110 is transferred to the placementtable 122 from the designated shelf plate. Alternatively, the pod 110may be transferred directly to the placement table 122 from the loadingport 114.

When the wafer entrance of the pod 110 placed on the placement table 122is pressed against the wafer loading/unloading port 120 of the frontwall 119 a of the sub-housing 119, the cap attaching/detaching mechanism123 detaches the cap of the pod 110 and the wafer entrance of the pod110 is opened. Thereafter, the wafer 200 is transported out of the pod110 by the tweezers 125 c of the wafer transport device 125 a via thewafer entrance, and aligned by the notch alignment device (not shown).The wafer 200 aligned by the notch alignment device is then loaded intothe standby space 126 provided behind the transfer chamber 124, and isloaded (charged) into the boat 217. After charging the wafer 200 intothe boat 217, the wafer transport device 125 a then returns to the pod110 and transports a next wafer of the plurality of the wafers from thepod 110 into the boat 217.

While the wafer transport mechanism 125 loads the plurality of thewafers including the wafer 200 from the placement table 122 of one ofthe upper and lower pod openers into the boat 217, another pod of theplurality of the pods is transferred to and placed on the placementtable 122 of the other of the upper and lower pod openers from therotatable pod shelf 105 by the pod transfer device 118, and the cap ofthe above-mentioned another pod is opened by the other of the upper andlower pod openers.

After the plurality of the wafers including the wafer 200 is completelyloaded (charged) into the boat 217, transport information is detected bythe wafer abnormality detection device 400. In order to detect thetransport information, as shown in FIG. 3, the wafer abnormalitydetection device 400 includes a configuration in which the pair of thedetection arms (for example, two detection arms) 401 is provided at thewafer transport device 125 a. As shown in FIG. 6, for example, the pairof the detection arms 401 is inserted below the wafer 200 placed on theboat 217, and is arranged such that the wafer 200 is supported by thepair of the detection arms 401. Thereafter, the wafer transport device125 a is sequentially moved upward and downward to a plurality of wafercrack detection points at lower surfaces of the plurality of the wafersin order to detect the transport information of the plurality of thewafers.

Thereby, for example, the presence or absence of the wafer 200 isdetected by a light shielding of the sensor S1, and the wafer jump-outof the wafer 200 is detected by a light shielding of the sensor S2. Inaddition, Further, whether or not the boat slot position is appropriateis detected based on a threshold level of the light shielding, and thecrack of the plurality of the wafers including the wafer 200 is detected(obtained) by comparing a displacement amount (deflection) of each ofthe plurality of the wafer crack detection points, or obtained from arelationship between the displacement amount and an allowable stress ateach of the plurality of the wafer crack detection points. In FIG. 6,the illustration of the tweezers 125 c is omitted.

When the boat 217 is inserted (loaded) into the process furnace 202, thelower end of the process furnace 202 is opened by the furnace openingshutter 147. Then, by elevating the seal cap 219 by the boat elevator115, the boat 217 is inserted (loaded) into the process furnace 202. Asa result, the plurality of the wafers including the wafer 200accommodated in the boat 217 is loaded into the process furnace 202.

After the plurality of the wafers including the wafer 200 is loaded intothe process furnace 202, the wafer 200 is processed in the processfurnace 202. For example, a process such as an oxidation process, afilm-forming process and a diffusion process is performed to the wafer200. After the wafer 200 is processed, the boat 217 is unloaded out ofthe process furnace 202 in an order reverse to that described aboveexcept for an aligning step of the wafer 200 by the notch alignmentdevice (not shown) and a wafer abnormality detection step performedafter the boat 217 is unloaded. Then, the pod 110 accommodatingprocessed wafers including the wafer 200 is transported out of thesubstrate processing apparatus 100, that is, out of the housing 111.

In the wafer abnormality detection step performed after the boat 217 isunloaded, as described later, before the processed wafers including thewafer 200 are transported out of the boat 217, a wafer abnormality (forexample, a wafer crack) is detected. For example, when the wafer crackis detected, a wafer with the crack (hereinafter, referred to as an“abnormal wafer”) whose transport state is abnormal and other wafersclose to the abnormal wafer are loaded to a transfer container differentfrom the pod 110 by the wafer transport device 125 a. Thereafter, anormal wafer without the crack is discharged (collected) from the boat217.

While the embodiments are described by way of an example in which thewafer abnormality detection step is performed after the boat 217 isunloaded, the embodiments are not limited thereto. For example, thewafer abnormality detection step may be performed after the plurality ofthe wafers including the wafer 200 is loaded into the boat 217 andbefore the wafer 200 is processed. When the wafer abnormality detectionstep is performed before the wafer 200 is processed, it is possible todetect the wafer crack of the plurality of the wafers including thewafer 200 before the plurality of the wafers is loaded into the processfurnace 202. As a result, it is possible to prevent an accidental losscaused by the wafer crack such as a lot-out. In addition, the waferabnormality detection step may be performed both after the plurality ofthe wafers including the wafer 200 is loaded into the boat 217 andbefore the processed wafers including the wafer 200 are transferred outof the boat 217 after performing a process such as a heat treatmentprocess to the wafer 200. When the wafer abnormality detection step isperformed both after the wafer 200 is loaded into the boat 217 andbefore the wafer 200 is transferred out of the boat 217, it is possibleto detect the wafer crack under the optimum conditions by obtainingreference data before the heat treatment process and by performing thewafer abnormality detection step after the heat treatment process.

As shown in FIG. 4, a substrate processing system 300 is provided with acomputer 302 configured to manage a plurality of substrate processingapparatuses including the substrate processing apparatus 100 orconfigured to analyze data. Each of the plurality of the substrateprocessing apparatuses is provided with a process module controller(hereinafter, also simply referred to as a “PMC”) 310. The PMC 310 isconnected to the computer 302 via a communication line 304 such as a LANfor communication. In general, the computer 302 performs operationmanagements of the plurality of the substrate processing apparatuses, orthe computer 302 is used to analyze the data transmitted from theplurality of the substrate processing apparatuses. In general, thecomputer 302 is installed outside a clean room where the plurality ofthe substrate processing apparatuses is provided.

As shown in FIG. 5, the PMC 310 may be constituted by a main controller312 and a sub controller 314. The main controller 312 may be constitutedby: an input/output device 306; a CPU (Central Processing Unit) 316; amemory device 317 serving as a storage device; a transmission/receptionprocessor 322 configured to transmit or receive data to or from thecomputer 302; and an I/O controller 324 configured to perform an I/O(input/output) control between the CPU 316 and the sub controller 314. Aconfiguration of the computer 302 may be substantially the same as thatof the main controller 312.

For example, the sub controller 314 may be constituted by: a temperaturecontroller 326 configured to control (adjust) an inner temperature ofthe process chamber 201 to a substrate processing temperature by aheater (not shown) provided on an outer periphery of the process furnace202; a gas controller 328 configured to control an amount such as anamount of a reactive gas supplied into the process furnace 202 based onthe output value (detected value) from a mass flow controller (MFC) 342provided at a gas pipe 340 of the process furnace 202; a pressurecontroller 330 configured to control an inner pressure of the processchamber 201 of the process furnace 202 to a substrate processingpressure by opening or closing a valve 348 or by controlling an openingdegree of the valve 348 based on the output value (detected value) of apressure sensor 346 provided at an exhaust pipe 344 of the processfurnace 202; a transfer controller 350 configured to control an actuatorof a substrate transfer system; and an abnormality determination part351 configured to determine the transport state of the plurality of thewafers including the wafer 200 based on the detected value of the waferabnormality detection device 400. For example, the abnormalitydetermination part 351 may be incorporated in the transport controller350.

For example, the memory device 317 may be constituted by components suchas a ROM (Read Only Memory) 318, a RAM (Random Access Memory) 320 and ahard disk (Hard Disk). For example, a recipe, various programs andreference data is stored in the memory device 317. According to theembodiments, master data (described later) measured in advance is storedin the memory device 317. Information for each of the plurality of thewafers including the wafer 200 (for example, wafer individualinformation, wafer type information, wafer transport information andwafer transport state correction information) is stored in the memorydevice 317 as the reference data. The wafer individual informationdescribed above refers to data obtained by editing a plurality ofinformation as a set. For example, the plurality of the information ofthe wafer 200 may include: a lot ID indicating a lot number of the wafer200; a pod slot number indicating a slot insertion position of the pod110; a boat slot number indicating a slot of the boat 217 designated bythe boat 217 for inserting the wafer 200; and a type of the wafer 200.In addition, the wafer type information of the wafer 200 refers toinformation indicating the type of the wafer 200, specifically,information indicating the type of wafer 200 such as a production wafer,a monitor wafer, a side dummy wafer and a supplementary dummy wafer. Thewafer transport information of the wafer 200 refers to informationindicating the transport state of the wafer 200 on the boat 217 obtainedfrom the wafer individual information of each of the plurality of thewafers including the wafer 200. In addition, the wafer transportinformation of the wafer 200 includes information on a determinationresult obtained by the abnormality determination part 351 by comparingthe detected data obtained by the sensor S1 provided on the pair of thedetection arms 401 with the master data measured in advance. Forexample, the information (that is, the abnormality information of thewafer 200) is roughly divided into a normal transport state or anabnormal transport state of the wafer 200. When the transport state isabnormal, the abnormality information of the wafer 200 may indicate theabnormal transport state such as a state in which an insertion depth ofthe wafer 200 inserted in the slot of the boat 217 is shallow and thewafer 200 jumps out from the boat 217 (hereinafter, also referred to asthe “wafer jump-out”), a state in which the wafer 200 is cracked(hereinafter, also referred to as the wafer crack), a state in which thewafer 200 is inserted into a slot of another boat instead of the slot ofthe designated boat 217 (hereinafter, also referred to as a “slotdifference”) and a state in which the wafer 200 is placed on the wafertransport device 125 a such that the slot of the designated boat 217 isleft empty (hereinafter, also referred to as an “empty slot”). When thetransport state is normal, the abnormality information of the wafer 200may indicate the normal transport state such as a state of “noabnormality”. In addition, the wafer transport state correctioninformation of the wafer 200 refers to information obtained bycorrecting the transport information of the wafer 200 when the wafer 200is in the abnormal transport state. Such correction is necessary inorder to combine the data on a hardware side of the substrate processingapparatus 100 and the data on a controller side of the substrateprocessing system 300 after the transport state of the wafer 200 isrecovered by the maintenance.

For example, the input/output device 306 may include: a display device334 configured to display information such as the data stored in thememory device 317; an input device 332 configured to receive an inputdata such as an input instruction of an operator (that is, a user) froman operation screen of the display device 334; a temporary memory device335 configured to temporarily store the input data received by the inputdevice 332 until the input data is transmitted to thetransmission/reception processor 322 by a display controller 336described later; and the display controller 336 configured to receivethe input data such as the input instruction through the input device332 and to transmit the input data to the display device 334 or thetransmission/reception processor 322.

For example, the display controller 336 is configured to receive aninstruction such as an execution instruction for executing an arbitraryrecipe among a plurality of recipes stored in the memory device 317 bythe CPU 316 via the transmission/reception processor 322. The displaydevice 334 is configured to display various display screens required fora substrate processing on the operation screen of the display device334. For example, screens for selecting, editing and executing a recipe,a screen for executing a command; a screen for executing a recovery anda screen for monitoring an operation status of the substrate processingapparatus 100 may be displayed on the operation screen by the displaydevice 334.

When a recipe created or edited by the input/output device 306 isexecuted on the operation screen, the sub controller 314 may refer tothe setting value of the recipe sequentially in the order of the stepsin the recipe. By feedback controlling the substrate transfer system ofthe substrate processing apparatus 100 and the actuator of the substratetransfer system, the substrate processing such as the oxidation process,the diffusion process and the film-forming process is performed to thewafer 200.

When transporting the wafer 200 to the boat 217 or transporting thewafer 200 from the boat 217 to the pod 110, the transfer controller 350is configured to refer to the wafer individual information (wafer ID)stored in advance in the memory device 317 and configured to controltransfer systems (substrate transfer systems) of the wafer transportdevice 125 a or the boat elevator 115 in order to transfer the wafer200. In addition, when the boat 217 is loaded into the process furnace202, the transfer controller 350 is configured to control the boatrotating mechanism 129 so as to rotate the boat 217 at a predeterminedspeed according to the recipe being executed.

After the plurality of the wafers including the wafer 200 is processedby executing the recipe and before the boat 217 is unloaded out of theprocess furnace 202, or before the boat 217 with the plurality of thewafers including the wafer 200 is loaded into the process furnace 202,the abnormality determination part 351 is configured to determine thetransport state of each of the wafers based on the result detected foreach of the plurality of the wafers including the wafer 200 by the waferabnormality detection device 400.

As shown in FIG. 6, according to the embodiments, for example, the wafer200 is detected by arranging the wafer 200 such that the wafer 200 issupported by the pair of the detection arms 401. Thereby, it is possibleto confirm whether there is no abnormality such as the tilt, the crack,the jump-out and the double stacking on the boat 217 and a predeterminednumber of wafers is placed at predetermined positions (grooves).However, as shown in FIG. 7, when the wafer 200 jumps out, the wafer 200may collide with or come into contact with the pair of the detectionarms 401 or the wafer transport device 125 a, which may increase thedamage.

As shown in FIG. 7, the boat 217 includes the plurality of the supportcolumns 220 (for example, three or four support columns), and the wafer200 is detected while the wafer transport device 125 a in a transferableposition relative to the boat 217 (that is, the position for thetransport to be performed) where the wafer transport device 125 a cantransport the plurality of the wafer including the wafer 200 to/from theboat 217. Since the plurality of the support columns 220 is provided,when the wafer 200 jumps out, the wafer 200 jumps out toward the wafertransport device 125 a. When the wafer 200 jumps out to a certainextent, the wafer 200 may be accommodated in the pair of the detectionarms 401, and it is possible to detect the jump-out of the wafer 200 bythe sensor S2.

However, when a jumping-out wafer 200 collides with the pair of thedetection arms 401, other wafers of the plurality of the wafers may beaffected, and the damage may be increased. According to the embodiments,as shown in FIG. 8A, the boat 217 is rotated by a predetermined angleand the plurality of the wafers including the wafer 200 is detected bythe pair of the detection arms 401. Specifically, since the locationwhere the wafer 200 jumps out can be detected as “no wafer” by thesensor S1 provided on the pair of the detection arms 401, it is possibleto confirm the abnormality as well as the crack of each of the wafers.In addition, it is necessary to operate the boat rotating mechanism 129and to acquire crack detection position data serving as the master datain advance so that the sensor S1 can detect the presence of each of thewafers including the wafer 200. As shown in FIG. 8B, similar to FIG. 6,it is possible to confirm whether there is no abnormality (such as thetilt, the crack, the jump-out and the double stacking) and thepredetermined number of wafers is placed at the predetermined position(groove). Thereby, it is possible to detect the crack of each of thewafers regardless of the wafer jump-out.

As described above, according to the embodiments, the boat 217 isrotated by the predetermined angle using the boat rotating mechanism 129and a crack detection is performed by the wafer detection device 400between the support columns 220 of the boat 217 at a location where thesensor S1 can avoid colliding with the plurality of the wafers includingthe wafer 200 or the plurality of the support columns 220 (that is, theposition where each of the wafers including the wafer 200 can bedetected by the sensor S1). Thereby, it is possible to perform thedetection of each of the wafers without contacting each of the waferseven when the wafer 200 jumps out. For example, the boat 217 may berotated by the predetermined angle so that the wafer transport device125 a is positioned at a center between the plurality of the supportcolumns 220 with respect to the boat 217.

First Embodiment

Hereinafter, a first embodiment in which the substrate processingserving as one of manufacturing processes of the semiconductor device isperformed using the substrate processing apparatus 100 preferably usedin the embodiments will be described. According to the first embodiment,the detection operation (wafer detection operation) by the pair of thedetection arms 401 of the wafer abnormality detection device 400 isexecuted after the boat 217 is unloaded out of the process furnace 202.In addition, the main controller 312 is configured to perform (execute)an exemplary sequence of the substrate processing shown in FIG. 10.

In performing the substrate processing, a substrate processing recipe(also referred to as a “process recipe”) corresponding to the substrateprocessing to be performed is loaded in, for example, the memory device317 in the main controller 312. Then, if necessary, an operationinstruction from the main controller 312 is transmitted to thecomponents of the sub controller 314 such as the temperature controller326, the gas controller 328, the pressure controller 330 and thetransfer controller 350. The substrate processing performed in this wayincludes at least a loading step, a film-forming step and an unloadingstep. According to the present embodiment, the substrate processingfurther includes a transfer step (and a substrate loading step oftransferring the plurality of the wafers including the wafer 200 to thesubstrate processing apparatus 100, which will be described later) and acollection step.

S101: Substrate Loading Step

When the main controller 312 receives a substrate loading instructionfrom an external management computer such as the computer 302, the maincontroller 312 starts a sequence of the substrate processing.Specifically, when the pod 110 is placed on the loading port 114 by anexternal transfer device, the main controller 312 issues a startinstruction (loading instruction) of the substrate loading step ofloading the pod 110 in the rotatable pod shelf 105 and transmits thestart instruction to the transfer controller 350. Then, the transfercontroller 350 controls the pod transfer device 118 to transfer the pod110 between the loading port 114 and the rotatable pod shelf 105.

S102: Transfer Step

Next, the main controller 312 issues an instruction of driving the wafertransport mechanism 125 to the transfer controller 350. Then, the wafertransport mechanism 125 starts the transfer of the plurality of thewafers including the wafer 200 from the pod 110 placed on the placementtable 122 to the boat 217 while following the instruction from thetransfer controller 350. The transfer of the plurality of the wafers isperformed until all the wafers scheduled to be loaded into the boat 217is loaded into the boat 217 (that is, the wafer charging is completed).

S103: Loading Step

When a predetermined number of the wafers (that is, the plurality of thewafers including the wafer 200) is loaded into the boat 217, the boat217 is elevated by the boat elevator 115 configured to operate accordingto the instruction from the transfer controller 350, and is loaded intothe process chamber 201 provided in the process furnace 202 (boatloading). When the boat 217 is completely loaded into the processchamber 201, the seal cap 219 of the boat elevator 115 closes the lowerend of the manifold of the process furnace 202 in airtight manner.

S104: Processing Step (Film-Forming Step)

Thereafter, a vacuum exhaust device (not shown) of the substrateprocessing apparatus 100 vacuum-exhausts the process chamber 201according to an instruction from the pressure controller 330 such thatthe inner pressure of the process chamber 201 reaches a predeterminedprocessing pressure (vacuum degree). In addition, the heater heats theprocess chamber 201 according to an instruction from the temperaturecontroller 326 such that the inner temperature of the process chamber201 reaches a predetermined processing temperature. Subsequently, theboat rotating mechanism 129 rotates the boat 217 and the plurality ofthe wafers including the wafer 200 according to an instruction from thetransfer controller 350. While the inner pressure of the process chamber201 is maintained at the predetermined processing pressure and the innertemperature of the process chamber 201 is maintained at thepredetermined processing temperature, a predetermined gas such as aprocess gas is supplied to the plurality of the wafers including thewafer 200 accommodated in the boat 217 in order to perform apredetermined process (for example, the film-forming process) to thewafer 200.

S105: Unloading Step

After the film-forming step S104 to the wafer 200 placed on the boat 217is completed, the boat rotating mechanism 129 stops the rotation of theboat 217 and the plurality of the wafers including the wafer 200accommodated in the boat 217 according to an instruction from thetransfer controller 350, and the seal cap 219 is lowered by the boatelevator 115 in order to open the lower end of the manifold. The boat217 with the processed wafers including the wafer 200 accommodatedtherein are then transferred (unloaded) out of the process furnace 202(boat unloading).

S106: Collection Step

Thereafter, the boat 217 with the processed wafers including the wafer200 accommodated therein are very effectively cooled by the clean air133 ejected from the clean air supply mechanism 134. For example, whenthe boat 217 is cooled to 150° C. or lower, the wafer detectiondescribed above is performed by the wafer abnormality detection device400. That is, the wafer abnormality detection device 400 detects theabnormality of the processed wafers including the wafer 200. When noabnormality is detected, the processed wafers including the wafer 200are transferred (discharged) from the boat 217 (wafer discharging).After the processed wafers including the wafer 200 are transferred tothe pod 110, other unprocessed wafers may be transferred to the boat217.

As shown in FIG. 9, the wafer detection by the wafer abnormalitydetection device 400 according to the present embodiment is performed byrotating the boat 217 in a rotation direction (indicated by arrows inFIG. 9) of the boat 217 by a predetermined angle A (or a predeterminedangle B) to a transferable position where the wafer 200 can betransferred to/from the boat 217 via a reference point (0°) such thatthe wafer 200 is moved to a crack detection position. Thereafter, thepair of the detection arms 401 provided at the wafer transport device125 a is slid into contact with the wafer 200 to be supported by thepair of the detection arms 401, and the measurement as shown in FIG. 8Bis performed.

The data of the crack detection position in the rotation direction (alsoreferred to as an “R-axis direction”) of the boat 217 is acquired inadvance as the master data. That is, both data when the wafer 200 isrotated by rotating the boat 217 to the position of the predeterminedangle A and the predetermined angle B as the crack detection positionare obtained. In addition, machine teaching is performed such that thesensor S1 provided on the pair of the detection arms 401 in the wafertransport device 125 a can detect the wafer 200, and the data on thetransferable position in which the wafer transport device 125 a cantransfer the wafer 200 is acquired as the master data. The master datais stored in the memory device 317.

As described above, the transfer controller 350 can rotate the boat 217to the crack detection position using the boat rotating mechanism 129with reference to the transferable position in which the wafer 200 canbe transferred, and the abnormality determination part 351 can detectthe wafer 200 at the position where the sensor S1 does not collide withthe plurality of the support columns 220 between the plurality of thesupport columns 220 of the boat 217. Therefore, it is possible toperform the detection of the wafer 200 (for example, a placement stateof the wafer 200) without contacting the wafer 200 even when the wafer200 jumps out.

As a result of the wafer detection by the wafer abnormality detectiondevice 400 according to the present embodiment, when the wafer 200 inwhich the abnormality occurs is detected, the abnormality determinationpart 351 is configured to control the transfer controller 350 such thatthe processed wafers including the wafer 200 are discharged from theboat 217 (wafer discharging) according to the content of theabnormality. Even when the abnormality such as the wafer jump-out hasoccurred, the abnormality determination part 351 can determines thelocation where the wafer 200 jumps out based on the measurement shown inFIG. 8B described above by reflecting the detection result of “no wafer”by the sensor S1.

According to the present embodiment, even when the abnormality hasoccurred in the wafer 200, the abnormality determination part 351 maycancel the wafer abnormality when the wafer 200 in which the abnormalityoccurs is removed or when the wafer 200 in which the abnormality occursand the wafers above and below the wafer 200 are removed so that thecause of the abnormality is eliminated. Then, the transfer controller350 controls the wafer transport mechanism 125 so as to collect othernormal processed wafers among the processed wafers from the boat 217.Thereby, it is possible to reduce the damage to the normal processedwafers due to the abnormality (particularly, the wafer jump-out).

The normal processed wafers stored in the pod 110 from the boat 217 aretemporarily stored in the rotatable pod shelf 105 from the placementtable 122, and then collected outside the substrate processing apparatus100. When all the normal processed wafers are transferred from the boat217 to the pod 110, the main controller 312 is configured to terminatethe sequence of the substrate processing. In addition, the collectionstep S106 may includes a step of transferring the normal processedwafers from the rotatable pod shelf 105 to the loading port 114 and astep of unloading the pod 110 used for the substrate processing from theloading port 114 to the outside of the substrate processing apparatus100. Then the main controller 312 may terminate the sequence of thesubstrate processing.

First Modified Example

According to the first embodiment, the wafer detection by the waferabnormality detection device 400 is performed by detecting the substrate(that is, the wafer 200) by rotating the boat 217 by the predeterminedangle A (or the predetermined angle B). However, according to the waferdetection by the wafer abnormality detection device 400 of a firstmodified example of the first embodiment, the boat 217 is rotated by thepredetermined angle A (or the predetermined angle B) to detect the wafercrack as in the first embodiment, and then the boat 217 is further moved(rotated) to the position of the predetermined angle B (by rotating byan angle obtained by subtracting the predetermined angle A from thepredetermined angle B) to detect the wafer crack. According to the firstmodified example, the same effects of the first embodiment describedabove may be obtained. In addition, according to the first modifiedexample, it is possible to detect microscopic change (for example,defects in a part of the wafer 200) that occurs in the wafer 200 than inthe first embodiment.

Second Modified Example

Since the wafer detection by the wafer abnormality detection device 400cannot be performed in a wafer transport position (that is, thetransferable position in which the wafer 200 is transferred) when thewafer 200 jumps out, according to the first embodiment, the waferdetection is performed after the boat 217 is rotated by thepredetermined angle A (or the predetermined angle B). As shown in FIG.7, when the wafer 200 jumps out after the boat 217 is rotated by thepredetermined angle A (or the predetermined angle B), the waferdetection cannot be performed. However, when no wafer among theprocessed wafers jumps out, it is possible to perform the waferdetection by the wafer abnormality detection device 400 in the wafertransport position.

Therefore, the wafer detection by the wafer abnormality detection device400 according to the second modified example may be performed asdescribed below. That is, the wafer crack is detected after the boat 217is rotated by the predetermined angle A, and then the wafer crack isdetected again after the boat 217 is further rotated reversely by thepredetermined angle A (or rotated by an angle obtained by subtractingthe predetermined angle A from 360°) to return to the wafer transportposition. According to the second modified example, the same effects ofthe first embodiment described above may be obtained. In addition,according to the second modified example, it is possible to detect amicroscopic change (for example, the defects in a part of the wafer 200)that occurs in the wafer 200 than in the first embodiment. In addition,since it is not necessary to return the boat 217 to a reference position(the left side of FIG. 9) after the wafer detection, it is possible tocollect the processed wafers including the wafer 200 immediately whenthere is no abnormality.

Second Embodiment

The wafer detection by the wafer abnormality detection device 400according to a second embodiment is performed after the transfer stepS102 of the substrate processing and before the loading step S103 of thesubstrate processing. Thereby, it is possible to detect the abnormalityof the wafer 200 before the wafer 200 is transferred (loaded) into theprocess furnace 202. As a result, a process of removing the wafer 200that involves the abnormality, a process of exchanging the wafer 200that involves the abnormality with a dummy wafer, or a process ofloading the wafer 200 that involves the abnormality onto the pluralityof the support columns 220 when the wafer 200 slightly jumps out may beperformed.

As described above, according to the second embodiment, a recoveryprocess such as the process of removing the wafer 200 that involves theabnormality may be performed according to the content of the detectedabnormality before loading the boat 217 into the process furnace 202,and the other normal wafers are loaded in the boat 217 by the subsequentloading step may be performed. Therefore, it is possible to continue thesubstrate processing while reducing the influence of the wafer 200 thatinvolves the abnormality.

The second embodiment may be combined with the first embodiment withouthindering the first embodiment. In addition, the second embodiment maybe combined with one of the first modified example and the secondmodified example. In addition, the second embodiment may be combinedwith at least one example selected from the first embodiment, the firstmodified example and the second modified example.

Third Embodiment

According to a third embodiment, a pitch of the tweezers 125 c of thewafer transport device 125 a is confirmed (checked) before performingthe transfer step S102 or the collection step S106. When an abnormalityof the tweezers 125 c is detected by confirming the pitch, the transferstep S102 (that is, the wafer charging) or the collection step S106(that is, the wafer discharging) cannot be performed until theabnormality of the tweezers 125 c is resolved.

According to the third embodiment, it is possible to prevent theabnormality in the transfer of the plurality of the wafers including thewafer 200 (for example, the collision of the tweezers 125 c with thewafer 200 and the falling-off of the wafer 200). As a result, it ispossible to perform the substrate processing without stopping thetransfer of the plurality of the wafers, and it is also possible toimprove the operating rate of the substrate processing apparatus 100.The third embodiment may be combined with the first embodiment includingthe first modified example and the second modified example or the secondembodiment without hindering the first embodiment or the secondembodiment. By combining the third embodiment with the first embodimentor the second embodiment, the same effects of the first embodiment orthe second embodiment may be obtained.

Fourth Embodiment

According to a fourth embodiment, during the transfer step S102 of thesubstrate processing, the wafer 200 placed on the tweezers 125 c of thewafer transport device 125 a is loaded into the slot (groove) of theboat 217, and the wafer transport device 125 a is temporarily stopped ata predetermined distance. Then, it is confirmed whether or not the wafer200 is placed on the tweezers 125 c. After confirming that the wafer 200is placed on the tweezers 125 c, the wafer transport device 125 a ismoved to the original position.

According to the fourth embodiment, it is possible to prevent thetransfer abnormality by confirming the presence or absence of a slidewafer (i.e., a wafer that has slid off from its normal position) in thetweezers 125 c. For example, even when the slide wafer is on thetweezers 125 c (even when the wafer 200 is placed on the tweezers 125c), the wafer transport device 125 a is stopped without moving to theoriginal position (the position at the start of transfer). Therefore, itis possible to prevent the falling-off of the wafer 200. In addition, itis possible to detect the slide wafer that may cause the wafer 200 tojump out or to be displaced even if the slide wafer does not fall off.In addition, when there is the slide wafer, it is possible toselectively perform an operation of loading the boat 217 again withoutmoving the wafer transport device 125 a to the original position.

As described above, according to the fourth embodiment, it is possibleto prevent the transfer abnormality without requiring a component suchas a sensor by stopping the wafer transport device 125 a temporarily ata predetermined distance from the loading position different from ainitial position (that is, the original position) after the wafertransport device 125 a moves from the initial position to the loadingposition and loads the plurality of the wafers including the wafer 200on the boat 217.

The fourth embodiment may be combined with the first embodimentincluding the first modified example and the second modified example,the second embodiment or the third embodiment without hindering thefirst embodiment, the second embodiment or the third embodiment. Bycombining the fourth embodiment with the first embodiment, the secondembodiment or the third embodiment, the same effects of the firstembodiment, the second embodiment or the third embodiment may beobtained.

Other Embodiments

While the technique is described in detail based on the above-describedembodiments such as the first embodiment, the second embodiment and thethird embodiment, the above-described technique is not limited thereto.The above-described technique may be modified in various ways withoutdeparting from the gist thereof.

For example, while the embodiments are described by way of an example inwhich the controller such as the PMC 310 is embodied by a dedicatedcomputer system, the controller is not limited to the dedicated computersystem. For example, the controller may be embodied by a generalcomputer system. For example, the controller may be embodied bypreparing an external memory device storing the above-described programand installing the program stored in the external memory device into thegeneral computer system. For example, the external memory device mayinclude a semiconductor memory such as a USB memory. However, the meansfor providing the program to the computer is not limited to the externalmemory device. The program may be supplied to the computer usingcommunication means such as the Internet and a dedicated line withoutusing the external memory device. The memory device 317 or the externalmemory device may be embodied by a non-transitory computer readablerecording medium. Hereafter, the memory device 317 and the externalmemory device are collectively referred to as the “recording medium”. Inthe present specification, the term “recording medium” may refer to onlythe memory device 317, only the external memory device or both of thememory device 317 and the external memory device.

For example, the above-described embodiments are described by way of anexample in which the substrate processing apparatus 100 is configured asa semiconductor manufacturing apparatus for manufacturing asemiconductor device. However, the above-described technique is notlimited thereto. The above-described technique may be applied to an LCD(Liquid Crystal Display) manufacturing apparatus for processing a glasssubstrate. In addition, the above-described technique may also beapplied to other substrate processing apparatuses such as an exposureapparatus, a photolithography apparatus, a coating apparatus and aprocessing apparatus using plasma.

The above-described technique may be applied to a substrate processingapparatus provided with a substrate detection mechanism configured todetect a transfer state of the substrate.

According to some embodiments in the present disclosure, withoutmodifying hardware of the configuration, it is possible to detect astate of the substrate without contacting the substrate with a mechanismconfigured to detect a state of the substrate.

What is claimed is:
 1. A method of manufacturing a semiconductor device,comprising: (a) processing a substrate placed on a substrate retainer;and (b) detecting a state of abnormality of the substrate placed on thesubstrate retainer after the substrate retainer is rotated by a firstangle with respect to a transferable position, wherein the substrate istransferable to/from the substrate retainer in the transferableposition.
 2. The method of claim 1, further comprising: (c) loading thesubstrate retainer, where the substrate is placed, into a reactionchamber; and (d) unloading the substrate retainer out of the reactionchamber after the substrate is processed.
 3. The method of claim 2,wherein (b) is performed before (a) is performed.
 4. The method of claim3, further comprising: (e) detecting the substrate placed on thesubstrate retainer while the substrate retainer is in the transferableposition, wherein (b) is performed before (e) is performed and after (c)is performed.
 5. The method of claim 1, further comprising: (e)detecting a crack of the substrate placed on the substrate retainerafter the substrate retainer is further rotated by a second angle. 6.The method of claim 1, further comprising: (f) detecting a crack of thesubstrate placed on the substrate retainer after the substrate retaineris further rotated reversely by the first angle.
 7. The method of claim1, further comprising: (g) cooling a transfer chamber where thesubstrate retainer and the substrate placed on the substrate retainerare disposed, wherein the substrate retainer is rotated by the firstangle in (b) after (g) is performed.
 8. The method of claim 7, wherein(b) is performed when a temperature of the substrate is equal to orlower than a predetermined temperature after (g) is performed.
 9. Themethod of claim 1, further comprising: (h) transferring the substrate tothe substrate retainer, wherein the substrate retainer is rotated by thefirst angle in (b) after (h) is performed and before (a) is performed.10. The method of claim 1, further comprising: (i) placing the substrateonto a substrate holder and transferring the substrate to the substrateretainer by the substrate holder, wherein, when an abnormality of thesubstrate retainer occurs before (i) is performed, (i) is suspendeduntil the abnormality is resolved.
 11. The method of claim 10, wherein atransport device provided with the substrate holder moves from aninitial position to a loading position where the substrate istransferable between the substrate retainer and the substrate holder,and is temporarily stopped after moving backward by a predetermineddistance from the loading position.
 12. A substrate processing apparatuscomprising: a rotating mechanism configured to rotate a substrateretainer capable of accommodating a substrate thereon; an abnormalitydetection device configured to detect an abnormality state of thesubstrate placed on the substrate retainer; a controller configured tobe capable of controlling the rotating mechanism and the abnormalitydetection device to perform: (a) processing the substrate placed on thesubstrate retainer; and (b) detecting a state of abnormality of thesubstrate placed on the substrate retainer after the substrate retaineris rotated by a first angle with respect to a transferable position,wherein the substrate is transferable to/from the substrate retainer inthe transferable position.
 13. The substrate processing apparatus ofclaim 12, further comprising: a substrate holder provided with atransport mechanism and configured to support the substrate; and a wafertransport mechanism configured to transfer the substrate holder and thesubstrate, wherein the abnormality detection device is provided at thewafer transport mechanism.
 14. The substrate processing apparatus ofclaim 12, further comprising: a pair of sensors provided at theabnormality detection device, wherein the abnormality detection deviceis further configured to detect a transfer state of the substrate by thepair of sensors based on a light shielding.
 15. The substrate processingapparatus of claim 12, further comprising: a plurality of sensorsprovided at the abnormality detection device, wherein at least onesensor among the plurality of sensors is configured to detect a presenceor absence of the substrate, and at least another sensor among theplurality of sensors is configured to detect a jump-out of thesubstrate.
 16. The substrate processing apparatus of claim 12, whereininformation indicating the abnormality state of the substrate is one of:a wafer jump-out, a wafer crack, a slot difference and an empty slot.17. The substrate processing apparatus of claim 12, further comprising:a substrate holder provided with a transport mechanism and configured tosupport the substrate; and a plurality of support columns provided inthe substrate holder, wherein a sensor is provided in the abnormalitydetection device so as not to collide with the plurality of supportcolumns and is configured to detect an abnormality state of thesubstrate placed on the substrate holder.
 18. The substrate processingapparatus of claim 17, further comprising: a wafer transport mechanismprovided at a center between the plurality of support columns.
 19. Thesubstrate processing apparatus of claim 12, wherein the controller isfurther configured to be capable of detecting a crack of the substrateplaced on the substrate retainer after the substrate retainer is furtherrotated by a second angle.
 20. The substrate processing apparatus ofclaim 12, wherein the controller is further configured to be capable ofdetecting a crack of the substrate placed on the substrate retainerafter the substrate retainer is further rotated reversely by the firstangle.
 21. A method of processing a substrate, comprising: (a)processing the substrate placed on a substrate retainer; and (b)detecting a state of abnormality of the substrate placed on thesubstrate retainer after the substrate retainer is rotated by a firstangle with respect to a transferable position, wherein the substrate istransferable to/from the substrate retainer in the transferableposition.
 22. A non-transitory computer-readable storage medium storinga program executable by a computer for performing the method of claim 1.